Cclibretion of the - ? - !>• M. Poole rnd 



Fsiary Settling Tube ^ ¥. S. Butcher 



for Si-nd Analysis 



LIST OF FIGURES 

 (all figures at end of paper) 



1. Scjaple data sheet for settling tube analyses. 



2. Ten settling tube analyses of the same saziiple. 



3. Six sieve analyses of the same sample. 



4,. Settling tube analyses of sixteen portions of the same sexid sample. 



5. Splitting procedure in obtaining sixteen portions of a single bulk 

 sample by combining alternate c^uarters. 



6. a^ S3ttling tube analyses of eight portions of spjae sand by combining 



alternate qucrtcrs. 



b. 'Settling tube analyses of eight portions of same sandf alternate 

 qxi3.Tter3 not combined. 



7. Settling tube analyses of four portions of sanie sand split to different 

 weights , 



8. Comparative cnalyses of sc^ne sample with end without material coarser 

 than 1 mia. 



9. a.. Percentage variation of the median diameter for a given percentage 



of fine material, 



b. Percentage variation of sorting for a given percentage of fine 

 material. 



10. a. Comparative analyses of same sample with and without fines 



(material < l/l6 mm = 7.7^). 



b. Comparative analyses of same sam.ple with exid without fines 

 (material < l/l6 mm = 22.5^). 



Abstract 



The accuracy of the Emerj'- Settling Tube for the analysis of send particles 

 has been investigated. As pointed out by Emery, this method is more rapid than 

 diy sieving aiid gives equivalent, or settling, diameters rather than geometric 

 diameters. It was felt that a more exact knowledge of the errors and limita- 

 tions of the method would be valuable. 



